The present disclosure relates generally to processes and devices for compacting divided materials to allow metering of the resulting compacted materials.
Well servicing fluid ingredients can often be in the form of divided material, such as powders, flakes and so forth. For example, polymers often can be purchased in divided material form, and are well known for use in oil and gas well treatment fluids, such as hydraulic fracturing fluids, packer fluids, and fluid loss control pills, as well as other applications. The polymers are generally mixed with a carrier fluid in a specific polymer to carrier fluid ratio in order to achieve desired fluid properties. The carrier fluid is often an aqueous based fluid, such as a brine, although other fluids, such as alcohols and other hydrocarbons, are also known.
Divided materials such as powders or flakes allow for ease of hydration. However, they can be difficult to accurately meter. One solution for addressing this problem in the past has been to mix a desired weight of, for example a polymer powder or flake, with a quantity of mineral oil to form a polymer slurry with known properties. Because the polymer slurry is a liquid, it can be accurately measured using liquid flow meters. The disadvantage of this method is the cost of the mineral oil and logistics of handling the polymer slurry.
Other known techniques for metering dry divided material, such as polymer powders or flakes, employ mechanical means, such as augers, vibrating feeders, loss-in weight feeders, or rotary air locks. While these mechanisms provide a degree of rate control, they fail to provide an accurate volumetric flow rate measurement of the dry product. Augers, vibrating feeders and rotary air locks provide volumetric flow measurements. However, these metering devices may not be as accurate due to, for example, variations in bulk densities of the divided material product.
Weight feeders, such as loss-in weight feeders, can be accurate assuming they are calibrated correctly. Even so, it would be advantageous to provide for a volumetric feeder with improved accuracy.
The present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the issues set forth above.